Solid-State Thermal Rectifier
C. W. Chang,1,4
D. Okawa,1
A. Majumdar,2,3,4
A. Zettl1,3,4*
We demonstrated nanoscale solid-state thermal rectification.
High-thermal-conductivity carbon and boron nitride nanotubes
were mass-loaded externally and inhomogeneously with heavy molecules.
The resulting nanoscale system yields asymmetric axial thermal
conductance with greater heat flow in the direction of decreasing
mass density. The effect cannot be explained by ordinary perturbative
wave theories, and instead we suggest that solitons may be responsible
for the phenomenon. Considering the important role of electrical
rectifiers (diodes) in electronics, thermal rectifiers have
substantial implications for diverse thermal management problems,
ranging from nanoscale calorimeters to microelectronic processors
to macroscopic refrigerators and energy-saving buildings.
2 Departments of Mechanical Engineering and Materials Science and Engineering, University of California at Berkeley, Berkeley, CA 94720, USA.
3 Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
4 Center of Integrated Nanomechanical Systems, University of California at Berkeley, Berkeley, CA 94720, USA.
* To whom correspondence should be addressed. E-mail: azettl{at}berkeley.edu
